nil pointer dereference panic

[jaekwon]

11:41:27 2013-12-10 [INF] BMGR: New valid peer 162.243.239.204:45765 (inbound)                                                                                                                            
panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xb code=0x1 addr=0x0 pc=0x4a7ebf]

goroutine 935 [running]:
runtime.panic(0x8c6a20, 0xf84c88)
        /usr/local/go/src/pkg/runtime/panic.c:266 +0xb6
github.com/conformal/btcwire.writeNetAddress(0x7fd81cb32b38, 0xc2111e1380, 0x80000011171, 0x0, 0x1, ...)
        /home/ubuntu/src/github.com/conformal/btcwire/netaddress.go:147 +0x4f
github.com/conformal/btcwire.(*MsgAddr).BtcEncode(0xc2110f2220, 0x7fd81cb32b38, 0xc2111e1380, 0x11171, 0x4, ...)
        /home/ubuntu/src/github.com/conformal/btcwire/msgaddr.go:109 +0x453
github.com/conformal/btcwire.WriteMessage(0x7fd81cb37590, 0xc2114321c8, 0x7fd81cb377f0, 0xc2110f2220, 0xd9b4bef900011171, ...)
        /home/ubuntu/src/github.com/conformal/btcwire/message.go:172 +0x326
main.(*peer).writeMessage(0xc21189e640, 0x7fd81cb377f0, 0xc2110f2220)
        /home/ubuntu/src/github.com/conformal/btcd/peer.go:910 +0x3f3
main.(*peer).outHandler(0xc21189e640)
        /home/ubuntu/src/github.com/conformal/btcd/peer.go:1128 +0x1d8
created by main.(*peer).Start
        /home/ubuntu/src/github.com/conformal/btcd/peer.go:1261 +0x271